Holographic gratings were thermally fixed in iron-doped photorefractive LiNbO3 crystals and developed with frequency-doubled Q -switched pulses of a Nd:YAG laser (light wavelength, 532 nm; pulse duration, 3 ns). The saturation values of the diffraction efficiency increased with increasing pulse light intensity. Compared with development with cw light, high-intensity laser pulse development resulted in an enlargement of the diffraction efficiency of a factor of ~2 . A contribution of the intrinsic defect Nb on Li site to the charge transport is most probably the origin of this effect. The results are useful, e.g., for improvements of volume holographic memories and wavelength filters.
© 1998 Optical Society of America
(120.2440) Instrumentation, measurement, and metrology : Filters
(160.3730) Materials : Lithium niobate
(160.5320) Materials : Photorefractive materials
(210.2860) Optical data storage : Holographic and volume memories
(230.1480) Optical devices : Bragg reflectors
S. Breer, K. Buse, and F. Rickermann, "Improved development of thermally fixed holograms in photorefractive LiNbO3 crystals with high-intensity laser pulses," Opt. Lett. 23, 73-75 (1998)